U.S. patent number 4,317,969 [Application Number 06/938,962] was granted by the patent office on 1982-03-02 for electrical line-connector.
Invention is credited to Hannes Riegler, Ulrich Wittwer.
United States Patent |
4,317,969 |
Riegler , et al. |
March 2, 1982 |
Electrical line-connector
Abstract
An electrical line-connector device for safety application. The
electrical contacts of the two-part line-connector which connect
electrical conductors with one another are flush contacts, which
come into contact when the connecting parts are brought together.
Each connecting part contains a part of a holding-magnet
arrangement which includes a permanent magnet, assuring the
holding-together of the connecting parts and the required contact
pressure. The one connecting part contains a switch device which is
formed in such a way that the flush contacts only carry voltage
when the connecting parts are placed together. The switch device
can be a familiar magnetic switch, which is switched on by the
permanent magnet in the other connecting part when the connecting
parts are placed together.
Inventors: |
Riegler; Hannes (3818
Grindelwald Cheminees Isolationen, Umbauten von Kuchen, BadN/A,
CH), Wittwer; Ulrich (3818 Grindelwald Cheminees
Isolationen, Umbauten von Kuchen, BadN/A, CH) |
Family
ID: |
25472292 |
Appl.
No.: |
06/938,962 |
Filed: |
September 1, 1978 |
Current U.S.
Class: |
200/52R;
200/51.09; 335/205; 439/39 |
Current CPC
Class: |
H01R
13/6205 (20130101); H01R 13/703 (20130101) |
Current International
Class: |
H01R
13/62 (20060101); H01R 13/70 (20060101); H01R
13/703 (20060101); H01H 021/00 () |
Field of
Search: |
;200/51.09,52R ;339/12R
;335/205,207 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
German Application, Offenlegungsschrift No. 2643031 Published Mar.
30, 1978..
|
Primary Examiner: Rubinson; Gene Z.
Assistant Examiner: Ginsburg; Morris
Attorney, Agent or Firm: Hessin; Robert M.
Claims
What is claimed is:
1. A safety connector for electrical connections with two mating
connector parts that fit together, each of which connector parts
contains contacts connected to electrical wiring, comprising:
first and second connector parts each having a planar contact face
for joining abutment and relative rotational positioning;
first and second contacts disposed in generally planar disposition
on the first contact face of said first connector part, said first
contact being central and said second contact being peripheral to
the first contact face;
first and second contacts disposed in generally planar disposition
on the second contact face of said second connector part, said
first contact being central and said second contact being
peripheral to said second contact face, said first central contact
being constituted of permanent magnet material;
spring loaded contact means disposed in said second connector part
to be magnetically attractable to electrically connect to said
central first contact of said first connector part when the planar
contact faces are placed in juxtaposition;
switch means in said second connector part connected to said
electrical wiring in current conductive mode only when said spring
loaded contact means is magnetically attracted; and
means for limiting the relative positioning of said first and
second connector parts between a first position wherein respective
first and second contacts of the first and second connector parts
are in electrical contact and a second position at least 90.degree.
displaced wherein the respective second contacts of said first and
second connector parts are not in conductive contact.
2. A safety connector as set forth in claim 1 which is further
characterized in that:
a contact plate means is disposed centrally in the contact face of
said second connector part; and
said spring loaded contact means is movable axially of said second
connector part to contact said contact plate means when
magnetically attracted.
3. A safety connector as set forth in claim 2 wherein said switch
means comprises:
a first normally open contact secured in electrically conductive
connection on said spring loaded contact means; and
contact terminal means secured insulatively on said second
connector part and being connected to said electrical wiring.
4. A safety connector as set forth in claim 1 wherein said second
contacts are arcuate contacts and said first contacts are centrally
disposed on said respective contact face in relation to said
arcuate contacts, said arcuate second contacts in each of said
first and second connector parts being in electrical communication.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention refers to a safety line-connector for electrical
connections with two matching connecting parts which fit together,
each of which contains contact pieces for connecting to wiring, and
one of which contains a switch mechanism through which at least one
of its contact pieces is connected with its wiring terminal only
when the connecting parts are fitted together.
2. Description of the Prior Art
The most common line-connectors are sockets and plugs of the most
various types. Such plug connections assure a good electrical
connection of the lines when the plug pins are seated right in the
sockets, but are in the simplest models not contact safe. In order
to attain sufficient contact safety with such simple outlets,
especially for playing children, the well-known safety disc inserts
have been developed, which, when inserted in the outlets, permit
access to the socket openings only after adjustment of a cover disc
held in the closed position by a spring. After somewhat more
frequent use, slight damage can already occur in the safety disc
inserts, which makes the insertion of a plug, which even normally
requires a certain skill, into a laborious task, so that the disc
inserts are frequently taken out again.
With plug devices for voltages above 250 V, the outlet is often
combined with a switch which must be turned off before the plug can
be withdrawn. The providing of switch contacts between sockets and
voltage-carrying lines provides a satisfactory degree of contact
safety for the outlets, and so it has also already been suggested
that a magnetic switch in the outlet be provided, which, for
example, is operable by a permanent magnet built into the plug, so
that when the plug is inserted into and withdrawn from the outlet,
the switch is automatically closed and opened, respectively, and
there is no voltage in the socket when the plug is not in it German
DE-OS No. 1 515 487).
Not only in trade and industry, but also otherwise in daily life
these days, a multiplicity of electrical appliances are used, which
are connected by cord and plug to outlets, often also to multiple
outlets. Every such "flying" line holds the danger that, for
example, when it is stumbled over, an appliance can be pulled from
the table, a lamp tipped over, etc., and/or plug and outlet
damaged, so that not only costly damages can arise, but it can also
result in an accident. The traditional plug devices therefore in no
way meet all safety requirements; not even when they are made safe
from contact.
It is an object of the invention to create a safety line-connector
which is not only safe from contact but also from the
aforementioned mechanical influences and the like, and which is in
addition simple to operate, cost-saving to produce and can also be
produced in small sizes.
The invention's solution to the task consists in the contact pieces
of the connecting parts being flush contacts, and each connecting
part having a part of a holding-magnet arrangement containing at
least one permanent magnet. The holding-magnet arrangement is
hereby so calculated that when the connecting parts are brought
together, a contact pressure sufficient for a secure contact
between the flush contact pieces is maintained, but the connecting
parts can be easily separated by an unintentional mechanical
influence, so that practically no damage can occur. Because of the
switch mechanism contained in the first connecting part, which is
connected, for instance, to a source of current, the line-connector
is contact-safe. The permanent magnet of the holding-magnet
arrangement is functionally contained in a second connecting part
connected, for example, to an appliance. The presence of this
permanent magnet makes it expedient to use a magnetic switch as
switching device, although any other switching device desired can
be used, as long as there is assurance that when the connecting
parts are separated the hot switch piece of the first connecting
part is kept free of voltage by the switch device.
In the further development of the invention, the holding-magnet in
the first connecting part, which contains the switch device, is
movable from an unoperated position in which the switch device is
set to break the connection between the contact piece and its
wiring terminal, into an operated position, in which the connection
between contact piece and wiring terminal is made and the permanent
magnet contained in the second connecting part serves to move the
holding-magnet part in the first connecting part. The movable
holding-magnet part is in the first connecting part preferably
arranged in a space closed off by a plate on the front of the
connecting part, so that neither dust nor moisture can penetrate
into the connecting part. In the further development of the
invention, with a simple line-connector especially suited for low
currents, the plate closing off the space with the holding-magnet
is itself a contact piece, and the permanent magnet contained in
the second connecting part and fitting to this plate carries the
opposite contact to this plate-contact piece, whereby when the
movable holding-magnet part is in the operated position, the
opposite contact is electrically connected through the contact
plate, the movable holding-magnet part and the switch device to its
wiring terminal. Such line-connectors can be produced in very small
sizes, as are common in many cases, especially for the connecting
of small appliances.
In a further development of the invention, both parts of the
holding-magnet arrangement are cylindrical bodies and each further
contact piece of the first and second connecting parts is a
ring-segment-contact concentric with the holding magnet part, so
that the line connector is polarized.
In the following Figures the invention is explained in more detail
with the use of examples of models, with reference to the attached
drawing. There we see:
FIG. 1 illustrates in schematic form a longitudinal section through
a line-connector after this invention, with a holding-magnet
arrangement which itself serves as part of the connection;
FIG. 2 is a perspective view of a multiple connecting part of a
line-connector after the invention;
FIG. 3 illustrates in schematic form a longitudinal section through
a line-connector after the invention, with a holding-magnet
arrangement and separate connecting contacts;
FIG. 4 illustrates in schematic form a line-connector with
grounding;
FIGS. 5a and 5b depict a further development of a line-connector
after the invention.
The safety line-connector shown in FIG. 1 in purely schematic form
is suitable, for instance, for the supplying of DC current to small
appliances such as transistor radios, calculators, etc., therefore
for rather wide use today. The one connecting part corresponding to
the outlet, in the following text referred to as "distributor part"
or "distributor" 1, and the other connecting part corresponding to
the plug, which is designated as "collector part" or "collector 2",
together constitute the line-connector. Frequently, several such
devices are connected simultaneously. FIG. 2 shows in perspective a
distributor element 3 with five distributor parts 7, which in the
present example can be connected to a converter delivering DC, or
be built onto the same. Because of the low voltage contact safety
is not required, although the distributor part must be short-proof.
An additional requirement here is the polarized nature of the
line-connector.
The distributor part 1 shown in FIG. 1 has a cylindrical housing
block 4 made of electrically insulating material, which contains a
center bore hole 5a, 5b, which is narrowed once. The front section
5a of the bore-hole, with the larger diameter, is closed off at the
front of the housing 4 with a relatively thin and electrically good
conducting plate 6, which constitutes in this model the one contact
pole of the distributor 1, and is therefore, for purposes of
satisfactory contact, preferably elastic and equipped with a
profile. The other contact pole of the distributor part 1 consists
of a contact ring 7, which is set into the front 4a of the housing,
surrounding the contact plate 6. On the rear, the housing 4 has a
first connecting terminal 8, which is electrically connected in the
housing 4 with the contact ring 7, and has, electrically insulated,
a second terminal 9, which as fixed contact of a switch device 11
is equipped for instance with a contact spring 10. The switch
device 11 is a special form of a familiar magnetic switch which in
a state of rest is held open by a retaining spring 12 and can be
closed by the placing of a permanent magnet on the housing, for
instance.
The magnetic switch 11 is here represented in the form of an
axially sliding piston in the center bore-hole 5a, 5b, whereby the
piston is the movable part of a holding-magnet arrangement. The
piston-shaped movable holding-magnet part 13 in the front bore-hole
section 5a consists of a magnetic material, iron, for instance, and
is brought by means of a rod 15 to the rear section 5b of the
bore-hole. The rod 15 has, as movable contact of the magnetic
switch 11, a contact bridge 16. The retaining spring 12 is arranged
here on the rod 15 between contact bridge 16 and housing 4. When
the piston-shaped clasp-magnet part 13 is pushed forward against
the force of the retaining spring 12 by means of a permanent magnet
placed outside on the contact plate 6, the holding-magnet part 13
lies next to the contact plate 6, and the contact bridge 16 is in
contact with the contact spring 10.
In the model in FIG. 1, the plate 6 is, as mentioned, the one
contact pole of the distributor part 1. When the magnetic switch 11
is closed, there is therefore voltage in the plate 6, and in order
to attain a small transitional resistance, the surface of the
holding-magnet part 13 of magnetic material is covered with a
good-conducting layer 14 of silver, for instance. The rod 15 of
electricity-conducting material such as copper or brass is in
electrical contact with the contact bridge 16.
The collector part 2 of the line-connector consists of a flat
housing 17 of electrically insulating and non-magnetic material
such as plastic, which has on its front surface 17a a preferably
flush permanent magnet 18 which fits to the plate 6 of the
distributor part 1 and a collector contact-ring 20 which
concentrically surrounds the permanent magnet 18 and fits to the
contact ring 7 of the distributor part 1. Since the permanent
magnet 18 is simultaneously the one contact pole of the collector
part 2, its surface is covered with a layer of a good electrical
conductor such as silver. In the housing 17 the two wires 21 and 22
are connected to the permanent magnet 18 and the contact-ring 20.
The collector part 2 can be very flat, whereby the permanent magnet
18, the contact-ring 20 and the connected ends of the wires 21, 22
can be cast in a plastic body, so that the result is a collector
part very sturdy in use and best suited for mass production.
The permanent magnet 18 of the collector part 2 and the piston
shaped holding-magnet 13 of the distributor part 1 are in regard to
the size and magnetic induction of the permanent magnet 18 so
calculated, that when the permanent magnet is placed on the plate
6, the collector part 2 adheres sufficiently firmly to the
distributor part 1, and the magnetic switch is held closed for a
secure contact. The clasp-magnet part 13 can likewise be a
permanent magnet, but it must be relatively weak, so that a piece
of iron laid on the plate 6 cannot close the switch 11.
The branch 1 is completely sealed off, so that neither dust nor
moisture can penetrate. The line-connector has a polarized design.
Since with the line-connector of FIG. 1 the current is carried
through the holding-magnet arrangement 13, 18, the line-connector
is usable for relatively weak-intensity currents.
A line-connector for high-intensity currents is shown in FIG. 3.
This line-connector is basically made like the one in FIG. 1, with
the distinction that here the current is not carried through the
holding-magnet arrangement 18, 13, and that the plate 6 of the
distributor part 1 as well as the permanent magnet 18 of the
collector part 2 are each surrounded by two concentric
contact-rings 23, 24 and 25, 26 respectively. With the distributor
part 1 the outer contact-ring 24 is connected with the terminal 8,
on which the neutral or the ground wire is to be connected. The
inner contact-ring 23 is connected to a fixed spring-contact 27,
which, for example, is arranged diametrically opposite to the
contact-spring 10 on the terminal 9. The rod 15 which has the
contact bridge 16 consists of electrically insulating material.
When the holding-magnet part 13, which can now be without a layer,
is pushed forward, the contact bridge 16 connects the contact
springs 10 and 27, so that there is then voltage on the inner
contact-ring 23. The distributor part of FIG. 3 is intended for
recessed mounting and has a cover plate 28. Polarity is also
assured with this model.
FIG. 4 shows a line-connector with grounding. The connector
corresponds to the one shown in FIG. 3, with the difference that
the distributor part 1 and the collector part 2 each have an
additional ground contact. In the model shown, the ground contact
of the distributor part 1 consists of a ground ring-contact 28
which is springy in the axial direction and stands out in front of
the front surface 4a, which contains the two contact-rings 23 and
24 and the plate 6. The collector part 2 contains a ground
ring-contact 29 which fits to the ring-contact 28. When the
collector part 2 is placed on the distributor part 1, the two
grounding rings 28 and 29 make at first a loose contact with each
other, and the magnetic switch 11 is opened. In order that the
magnetic switch 11 closes, the permanent magnet 18 must be placed
on the plate 6 of the distributor part 1; that is, the collector
part 2 must be pressed against the spring force of the grounding
ring 28 onto the distributor part 1. With this pressing the ground
connection is made secure. Only after that does the magnetic switch
11 close. The ground ring-contact 28 can also be fixed in
distributor part 1 and a springy ground ring-contact 29 be provided
in collector part 2. The one ground ring-contact can also be
replaced by grounding pins.
In the models described, the current-carrying contacts are in the
form of ring-contacts. These contacts can of course also be given
any other form desired.
FIG. 5a shows the front side 4a of a distributor part 1 which
corresponds to FIG. 1, in which the contact-ring 7 of FIG. 1 is
divided into two ring segments 7a, which lie diametrically opposite
to each other. FIG. 5b shows in perspective the line-connector with
the applied collector part 2, which instead of the contact ring 20
of FIG. 1, contains two contact pieces 20a which fit on the
contact-ring segments 7a. With this line-connector there are two
positions, I and II (FIG. 5b). In position I the contact pieces 20a
of the collector part 2 are against the contact-ring segment 7a of
the distributor part 1, so that when the magnetic switch is turned
on, the connected wires 21, 22 carry current. In position II on the
other hand, these contacts are not against each other, so that the
wires 21, 22 carry no current. If with such a model of the
line-connector the collector part 2 is made so that it can be
turned on the distributor part 1 to the positions I and II (FIG.
5b), then the line connector receives an additional switching
function; that is, in order to turn off a connected appliance, the
line-connector need not be separated.
Changes may be made in the combination and arrangement of elements
as heretofore set forth in the specification and shown in the
drawings; it being understood that changes may be made in the
embodiments disclosed without departing from the spirit and scope
of the invention as defined in the following claims.
* * * * *